Yes, and the markings are not of much value.
> except on the Unimat SL-1000 which had only a
I assume that most lathes use a rack and worm gear to reserve the
leadscrew for threading, right???
I thought of that, and it is indeed a possibility for the future.
However, given the responses in this thread, it appears that I will not
have much trouble over it. I simply did not want to tell myself that
and regret it later.
I was afraid someone would use the J-word :) Having had trouble with
them in the past, I doubt I would even consider a Jet machine. I _hope_
I would not even consider a Jet machine. I think I would sooner buy
another Buick. The hostility is of course *not* directed at you, and
your point is well-taken.
The Grizzly version of the lathe in question appears to be exactly the
same base with some nice looking dials and handles and some paint. I am
waiting for a response from them about the dials, but would probably
have to wonder whether they are indeed a metric "equivalent." Also, we
have Richard's "friend of mine" comment, and so far no such favorable
review of a Grizzly.
However, the question stands: if anyone knows of a true 10 tpi lathe in
the same class, I will take a look as I am doing with the Grizzly. So
far, I am leaning toward keeping the machine.
Indeed. If you want precision in longitudinal motion, you clamp
either a turret bed stop or a dial indicator to the bed parallel to the
ways. You could do with a micrometer bed stop and a set of spacers if
you don't need it very often.
Yes -- except that the inexpensive ones are likely to use the
leadscrew's threads for feeds too -- requiring more changing of speeds
to get to a fine enough feed. As examples:
1) The Atlas/Craftsman 6x18 lathe (long out of production) -- had only
the leadscrew and a basket of change gears. You used the
half-nuts for both feed and threading, and if the change gears
were set up for threading they would be too fast for practical
feed if you are after a nice finish. So -- you could not even
get away with a "good enough" and leave the gears set as they
2) My 12x24" Clausing (also long out of production) has both a
quick-change gearbox making it easier to change feeds and speeds
(and less messy -- you wind up with rather black hands changing
gears frequently if you keep them properly lubed), and separate
feed controls on the apron. This machine used the same
leadscrew to power the feeds, but not the threads on the
leadscrew. Instead, it had a keyway milled in the side of the
leadscrew the full length. The apron had a sleeve in bearings
which surrounded the leadscrew with a key engaging the keyway,
and a worm gear on the OD of the sleeve. Gears in the apron
picked up the rotation of the leadscrew through the worm and
were carried to either the handwheel to move the carriage via
the rack and pinion (and much slower than the half-nuts would at
the same speed so you don't need to change feed gears as much),
or to the cross-feed (even slower for fine finish when facing
Fancier systems would have a separate rod with the keyway for
the feed, and sometimes a second leadscrew and half-nut set for metric
threading instead of Imperial threading. I would like to have this
capability. Metric threading really should have a metric thread
leadscrew to allow the threading dial to be useful.
O.K. I have made mistakes using the 0.125"/rotation handwheels
on the machine at work before I retired. I prefer the 0.100"/rotation
on my Clausing. But I do have an inexpensive DRO (The Shooting Star)
which I plan to eventually mount on the Clausing. Among the advantages
are accurate position even when leadscrews are badly worn, and the
ability to switch the readout between reading diameter removed and
reading radius removed depending on what you need to do. As it is, I
keep a digital caliper and an HP-15C calculator handy for keeping track
of what dimension I am sneaking up on. I tend to zero the calipers at
the target diameter so my readings tell me how much needs to be removed,
and the divide the reading by two to get the necessary dial reading
Just which model of Jet did you have problems with? The lathe
which I used was essentially the brother of yours -- same castings and
features, and those had a pretty good reputation compared to the 9" and
7" ones, which were very limited.
Note that an 8 TPI thread works out to precisely 3.1750 mm thread
pitch -- not exactly the most convenient value, but precise. :-)
At this point -- why not keep it? I don't think that you will
find anything with a 10 TPI cross-slide leadscrew which is not made in
the USA -- which mostly means older machines like my 12x24" Clausing,
which was made in 1957.
Email: < email@example.com> | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
That seems like an obvious solution to the problem. The lathe of the
hour has a separate shaft with keyway to drive the feeds.
No question about that.
The big example is an H/V bandsaw. My real gripe is their reaction to
my pointing out a serious design flaw in the emergency cutoff. They
really showed their colors on it, and it did fail as I predicted.
Prior to that, I bought one of their woodworking jigs. Never again.
I am leaning toward keeping it. I would have preferred to hash this out
pre-purchase, but this has been a helpful discussion, and if I do keep
it, it won't be because I made foolish assumptions about how I will use
the dials. It sounds like the primary deficiency will be in setting
dials to agree after a witness cut, but I can create a chart for
converting diameter to dial readings to simplify it.
I couldn't resist pulling your leg! However, the remark had some validity. My
dials mean nothing to me until I start getting close to where I need to be, and
then nothing when I get really, really close. I guess it depends on what the
job is but I rely on my measuring device and an intuitive twist of the screw.
Exactly what I do on a mill, but the difference is that "caring" usually
means matching the dial to the last two digits on the drawing. If those
walked every revolution, I'd go nuts. If most work "take another
0.011," then the dial range is not a big deal.
I'd just accept it and move on. I have used a lot of lathes. Each one is a
bit different and you quickly adapt to it. The diameter of your dials have
an effect too on how fine you can position the cross slide. Big ones are
nicer than small diameter ones. We are only talking 25% coarser in pitch
Now what really irritates me is that every lathe I've used except for mine,
pulling up on the half nut lever disengages the split nuts :(
"Additionally as a security officer, I carry a gun to protect
government officials but my life isn't worth protecting at home
in their eyes." Dick Anthony Heller
I personally think the lathe is junk. How many spindle speeds do you have
?(probably 9), you need 12. How fast is the slowest speed in back gear? You
really need around 30 rpm. You probably have around 90 rpm and that is too
fast for a 12" machine. How many threads will it cut? (38). A good machine
will cut 80 in inch alone. An inch machine will have a 4 or 8 TPI lead screw
for the carraige and a 10 TPI for crossfeed and compound. The good chinese
machines have dual graduations on the carraige and compound both inch and
metric. Most metric machines have .02 graduations. Check the thread dial.
You probably have a metric machine. If you elect to keep it, you MUST
completely dissassemble it and clean it. It will be full of chips, swarf and
grit. Assume nothing, check everything including spindle parrallelism to the
bed ways. You get what you pay for. If you ever get a chance to use a class
machine, you will never own the one you just bought.
Please do not get me wrong. I am not prejudiced against Chinese machines.
They are great value for money, but you need to understand what you are
buying. I have had very good luck with some, but I have really seen some
junk. Buyer beware! The good machines are usually made in Taiwan and the
junk made on the mainland, but that rule is very gray now with the much
larger trade between Taiwan and the mainland. I have witnessed extensive
trade volume with China through a close associate. On some lots of
machinery, we have seen 1 in 4 received as failures in some shape or form!
Worst of all, most resellers never carry parts. Do not expect after sales
On Sun, 27 Apr 2008 12:34:18 -0500, with neither quill nor qualm,
Then you haven't been buying them here for long enough, Ig.
Happiness in marriage is entirely a matter of chance. If the dispositions
of the parties are ever so well known to each other or ever so similar
beforehand, it does not advance their felicity in the least. They always
continue to grow sufficiently unlike afterwards to have their share of
vexation; and it is better to know as little as possible of the defects of
the person with whom you are to pass your life.
-- Jane Austen, Pride and Prejudice, 1811
Well I have not seen a junk tools made either here or in Europe. Of course,
some are better than others, but never junk. However, it stands to reason
that there must be some junk made in the first world even if I haven't seen
it, but it sure in hell isn't 1 to 4, which I see regularly from mainland
On Sun, 27 Apr 2008 12:34:18 -0500, Ignoramus30765
Neither have I, actually...and Im pretty tool savvy.
Political Correctness is a doctrine fostered by a delusional,
illogical liberal minority, and rabidly promoted by an
unscrupulous mainstream media, which holds forth the
proposition that it is entirely possible to pick up a turd by the clean end.
On Sun, 27 Apr 2008 17:31:29 -0500, with neither quill nor qualm,
If nothing else, you never bought anything from Searz branded Crapsman
in the late 70s or early 80s, or anything not branded Crapsman at any
other time. Then again, lots of that crap is Chiwanese or Indian, and
both those sources have been producing a MUCH better product in the
last decade or so.
As a curmudgeon, I grok that in its entirety.
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